I know next to nothing about real estate, so I want to know if this is normal. DF and I are looking at buying a house. I requested to view one from an agent and he asked if I would be willing to sign an agreement that I wouldn't work with another company. That seems outrageous to me, especially when all I did was request a viewing. "Hey, I know this is the first date, but let's get married tomorrow!" That's what it feels like to me.
I think it depends on the area in general and the broker/agency. But, it can benefit you with the right agent. If you sign an agreement with an agent as a buyer, they should do a LOT of work for you. You tell them the particulars of what you want (area, size, price, etc.) and they go through the listings for you, come up with a few to show you and take you through those houses.
This works particularly well if you have a limited amount of time in an area that you are not familiar with. They know the area and they have the inside information on the market.
The times we have done this, we've set up showings and signed the contract then. They are not going to do all this work for you without knowing they will be paid for it when you buy a house.